This disclosure relates generally to the transport of perishable goods and, more particularly, to the preparation of a refrigerated cargo box for transport of a non-refrigerated product on a return leg of a transport haul after delivery of a refrigerated product.
Refrigerated trucks, trailers and mobile containers are customarily equipped with a transport refrigeration unit operatively associated with the cargo box of the truck, trailer or mobile container for cooling the atmosphere within the cargo box. The transport refrigeration unit includes a refrigerant vapor compression system having a refrigerant evaporator heat exchanger. When transporting temperature sensitive perishable goods, ranging for example from fresh products, such as produce, meat and fish to frozen goods, such as deep frozen seafood, air from within the cargo box of the truck, trailer or container, is circulated through an evaporator heat exchanger in heat exchange relationship with refrigerant circulating through the refrigerant vapor compression system. Box air is drawn from the cargo box, referred to as return air, passed through the evaporator heat exchanger of a refrigeration vapor compression system of the transport refrigerant unit to cool the box air, and then circulated back to the cargo box. The air circulated back to the cargo box is referred to as supply air.
After a refrigerated perishable product is delivered and unloaded from the cargo box of the truck, trailer or container, the truck, trailer or container may be hired to haul non-refrigerated perishable, dry product, such as for example, but not limited to, bags of flour or sugar or other dry goods for the return leg. In such case, it is customary to wash out the cargo box of the truck, trailer or container. The cargo box must then be allowed to dry out prior to loading the non-refrigerated perishable, dry product. Depending upon local ambient conditions, the natural drying of the cargo box may take several hours, resulting in delays in loading and departure, costly downtime, poor equipment utilization rates, scheduling issues, and general lack of productivity.